From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: PROBLEM: Xen ballon driver seems to be broken in 2.6.26 Date: Tue, 22 Jul 2008 11:02:32 -0700 Message-ID: <488620B8.80600@goop.org> References: <200807221812.21346.nice@titanic.nyme.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <200807221812.21346.nice@titanic.nyme.hu> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: =?ISO-8859-15?Q?N=E9meth_Tam=E1s?= Cc: xen-devel@lists.xensource.com, jeremy@xensource.com List-Id: xen-devel@lists.xenproject.org N=E9meth Tam=E1s wrote: > I use openSUSE 10.3 both for dom0 and domU, but the kernels and the ent= ire Xen=20 > system (hypervisor, tools and dom0 kernel) is replaced by the newest ve= rsion=20 > downloadable from xen.org. Every component is compiled from source. The= =20 > hypervisor is 64 bit, and the dom0 and domU systems are 32 bit, PAE. Th= e domU=20 > kernel is the vanilla 2.6.26. It's OK, that migration, save, restore, e= tc.=20 > don't work, as you plan the support for these features to be included i= n=20 > 2.6.27 AFAIK. (BTW, when will you include the domU support for x86_64 a= nd CPU=20 > hotplug?) But: > > The balloon driver also seems to be broken. If i decrease the amount of= memory=20 > in domU, it becomes immediately almost unresponsive. I can ping the dom= U, and=20 > even Xvnc continues to operate (the "screen" of domU changes, the KDE c= lock=20 > continues to count the seconds), but i cannot start new programs. Sadly= it=20 > includes the fact that i can't even run dmesg. Neither the output of 'x= m=20 > console' gives any error message. When i destroy and restart the domU = then,=20 > i cannot find anything about the crash in /var/log/messages. When i try= to=20 > start a new program, then the domU totally hangs finally, the KDE clock= =20 > stops, and it cannot be shut down (only destroyed). > =20 So that's consistent with the balloon driver over-aggressively shrinking=20 the domain, until there's no memory left to do anything. The balloon=20 driver has no safety checks to prevent that from happening. What value are you setting the target size to? Are you using the right=20 units? J